hi, this may be true, but it 'volume' that is deposited and not weight. the specific gravity of palladium is 12; the specific gravity of gold is 19.3. so for equal thicknesses of deposit, palladium is the better deal. phil -----Original Message----- From: Eric Yakobson [mailto:[log in to unmask]] Sent: Friday, January 29, 1999 10:57 AM To: [log in to unmask] Subject: Re: [TN] Palladium underplate for Cu-Ni-Au system Hi Benny, The irony is that these days palladium is more expensive then gold. In today's paper the prices are: Gold -- $283.30 troy oz. Palladium -- $331.75 troy oz. (almost as bad as Platinum -- $344.10). Eric Yakobson Alpha PC Fab "Au Po Lam Benny" <[log in to unmask]> on 01/28/99 11:13:50 PM To: [log in to unmask] cc: (bcc: Eric Yakobson/AlphaPCFabUS/Cookson) Subject: [TN] Palladium underplate for Cu-Ni-Au system Hi technetters, Does anybody know the purpose of a palladium layer between the Ni and Au for wire bonding PCB? Recently, I've got a request to bond gold wire (thermosonic) on PI flex which is plated with electroless Ni and immersion Au. On one sample, the gold thickness is reduced and compensated by a electroless palladium layer above Ni; while the other just is the normal electroless Ni and immersion Au. The phosphorus contect is around 6-8%. I would appreciate if anyone can advise me on the palladium function, cost implication (cheaper by reducing the gold?), and bondability of this kind of metalization. Regards, Benny. ASM Assembly Automation Email :[log in to unmask] ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################ ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################ ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################